Fibromyalgia Unveiled – Kick Off

Some people try to make us believe fibromyalgia(1) is incomprehensible, mythical, with unclear pathogenesis, difficult to diagnose, untreatable, incurable; but is this true?


Is it a new disease? Only the medical term fibromyalgia has been coined recently, the disease itself has been know centuries (you might have heard of the the tale about the princess on the pea), or you have read that Sir William Gowers called it fibrositis by in 1904, not knowing then that fibromyalgia isn’t an inflammatory disese. Fibromyalgia is a medical term, which is constructed out of Latin fibro- (fibrous tissues), Greek myo- (muscle), and Greek algos-(pain), thus meaning pain in muscle and connective tissue.


How come fibromyalgia is classified by the ICD [International Classification of Diseases 10] as M79.70 and therefore rheumatologists make the diagnosis? Not very long ago rheumatologists were confronted with the complaints of patients that looked like a rheumatic disease (myalgia, arthralgia, fatigue, non-restorative sleep, morning stiffness, and more), but they couldn’t find any lab test or X-ray deviation that lead to a diagnosis. What they found, however, was wide spread pain and tenderpoints. The concept of fibromyalgia was introduced by H.A. Smythe and H. Moldofsky [Smythe HA, Moldofsky H. Two contributions to understanding of the "fibrositis" syndrome. Bull Rheum Dis. 1977;28:928-931]. During the following years rheumatologists came together at an ACR [American College of Rheumatology] meeting and decided, lets look more thoroughly into this disease. To make comparison between studies possible and therefore promote research, they defined classificatory criteria – the 1990 ACR Criteria for Fibromyagia. These criteria aren’t that difficult, but aren’t “generally utilized by nonrheumatologists, and rheumatologists may diagnose fibromyalgia in patients who do not satisfy the ACR criteria”. The criteria are simple: Widespread pain for at least 3 months and painful tender points on pressure at 11 (minimum) of 18 specified sites of the body. Pressure was difined further to be 4 kp/cm2. These criteria were a major advance as they standardized the definition of fibromyalgia for research. To be used outside of studies as a diagnostic tool in routine practice was never intended, but has lead to the myth fibromyalgia was a peripheral disease.


Take home messages: fibromyalgia can be diagnosed and is classified by the ICD as M79.70



(1) fibromyalgia - short for fibromyalgia syndrome, abbreviated as FMS

OT: I took a course with Dr. Smythe in the 1990ies.